Vaillant Ecotec 637

[sunny71]

Hi,

I have recently had a Vaillant Ecotec 637 installed with a Santon premier plus Cylinder (unvented system). The installation was part of a bigger project and I now need to verify a couple of things so would be grateful for any help.

1. Does the boiler live need to be in permanent live slot 1 of a S-plan or slot 10? The reason for asking is due to the fact that when the external controller has CH and DHW switch off the whole boiler is off (no display, as if mains power is switch off). I suspect it should be permanent live but all the s-plan drawing have it in slot 10.. Please help

2. I also have an external room stat which is wired up as per S-plan drawings, however, in the ecotec there is a bridge between pins 3 and 4 inside the ecotec's electronic control box. Should this bridge be removed and wired into the control box as follows pin 3 = Perm Live ( Grey)
4 = Switch Live (Orange)
5 = Neutral (blue)

I would appreciate any guidance,

Thanks

Sunny

 

[Agile]

As explained on the phone the boiler needs a permanent live to give frost protection and pump over run.

In your application the room stat should be wired as it is to the control circuit and not to the boiler.

What did not get discussed on the phone is that as you have an unvented cylinder that has to be fitted by someone with a suitable qualification and also notified to Building Control just like the boiler!

Tony

 

[gas4you]

Permanent live needs to come from terminal 1 on the honeywell wiring block whilst the switched live is usually from terminal 10, or whichever terminal the 2 orange wires from the zone valves go to and goes to terminal 4 on the ecotec pcb.

Remove the link from 3-4